在实际应用中，经常会遇到上传Excel或者下载Excel的情况，比如导入数据、下载统计数据等等场景。针对这个问题，我写了个基于SpringMVC的简单上传下载示例，其中Excel的处理使用Apache的POI组件。
主要依赖的包如下：
<dependency> <groupId>commons-io</groupId> <artifactId>commons-io</artifactId> <version>2.4</version> </dependency> <dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3.1</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>4.0.0.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>4.0.0.RELEASE</version> </dependency> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi</artifactId> <version>3.10.1</version> </dependency>
相关处理类：
（一）Controller类
package com.research.spring.controller; import java.io.IOException; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.apache.poi.ss.usermodel.Row; import org.apache.poi.ss.usermodel.Sheet; import org.apache.poi.ss.usermodel.Workbook; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.multipart.MultipartFile; import org.springframework.web.servlet.ModelAndView; import com.research.spring.model.UserInfo; import com.research.spring.view.ExcelView; @Controller @RequestMapping("/file") public class FileController { /** * Excel文件上传处理 * @param file * @return */ @RequestMapping("/upload") public ModelAndView uploadExcel(@RequestParam("file") MultipartFile file){ List<UserInfo> list = new ArrayList<UserInfo>(); //这里只处理文件名包括“用户”的文件，模板使用下载模板 if( file.getOriginalFilename().contains("用户") ){ try { Workbook wb = new HSSFWorkbook(file.getInputStream()); Sheet sheet = wb.getSheetAt(0); for( int i = 1; i <= sheet.getLastRowNum(); i++ ){ Row row = sheet.getRow(i); UserInfo info = new UserInfo(); info.setUserName(row.getCell(0).getStringCellValue()); info.setPassword(row.getCell(1).getStringCellValue()); list.add(info); } } catch (IOException e) { e.printStackTrace(); } } ModelAndView mav = new ModelAndView("content"); mav.addObject("content",list.toString()); return mav; } /** * Excel文件下载处理 */ @RequestMapping("/download") public ModelAndView downloanExcel(){ List<UserInfo> list = new ArrayList<UserInfo>(); UserInfo userInfo = new UserInfo(); userInfo.setPassword("0000"); userInfo.setUserName("sdfas"); list.add(userInfo); list.add(userInfo); list.add(userInfo); list.add(userInfo); Map<String,List<UserInfo>> map = new HashMap<String, List<UserInfo>>(); map.put("infoList", list); ExcelView ve = new ExcelView(); return new ModelAndView(ve,map); } } （二）实体类
package com.research.spring.model; public class UserInfo { private String userName; private String password; public String getUserName() { return userName; } public void setUserName(String userName) { this.userName = userName; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } @Override public String toString() { return "UserInfo [userName=" + userName + ", password=" + password + "]"; } } （三）View类
这个类在下载时用到，在Spring渲染页面时使用自定义的View类进行Excel的相关处理。
package com.research.spring.view; import java.io.OutputStream; import java.net.URLEncoder; import java.util.List; import java.util.Map; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.apache.poi.ss.usermodel.Cell; import org.apache.poi.ss.usermodel.Row; import org.apache.poi.ss.usermodel.Sheet; import org.springframework.web.servlet.view.document.AbstractExcelView; import com.research.spring.model.UserInfo; /** * 下载Excel视图 * * @author wdmcygah * */ public class ExcelView extends AbstractExcelView { @Override protected void buildExcelDocument(Map<String, Object> model, HSSFWorkbook workbook, HttpServletRequest request, HttpServletResponse response) throws Exception { @SuppressWarnings("unchecked") List<UserInfo> list = (List<UserInfo>) model.get("infoList"); if (list != null && list.size() != 0) { int len = list.size(); Sheet sheet = workbook.createSheet(); // 第一行文字说明 Row row = sheet.createRow(0); Cell cell = row.createCell(0, Cell.CELL_TYPE_STRING); cell.setCellValue("用户名"); cell = row.createCell(1, Cell.CELL_TYPE_STRING); cell.setCellValue("密码"); //下面是具体内容 for (int i = 0; i < len; i++) { row = sheet.createRow(i + 1); cell = row.createCell(0, Cell.CELL_TYPE_STRING); cell.setCellValue(list.get(i).getUserName()); cell = row.createCell(1, Cell.CELL_TYPE_STRING); cell.setCellValue(list.get(i).getPassword()); } } response.setContentType("application/vnd.ms-excel"); response.setCharacterEncoding("utf-8"); //这里对文件名进行编码，保证下载时汉字显示正常 String fileName = URLEncoder.encode("用户.xls", "utf-8"); //Content-disposition属性设置成以附件方式进行下载 response.setHeader("Content-disposition", "attachment;filename=" + fileName); OutputStream os = response.getOutputStream(); workbook.write(os); os.flush(); os.close(); } } （四）主要配置文件
上传文件时需要在配置文件中配置MultipartResolver类，配置后Spring会自动将文件传成MultipartFile对象，然后就可以进行相应的处理。示例看Controller类。
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:util="http://www.springframework.org/schema/util" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd"> <context:component-scan base-package="com.research" /> <bean> <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" /> <property name="prefix" value="/WEB-INF/" /> <property name="suffix" value=".jsp" /> </bean> <!-- 上传文件解析器配置 --> <bean id="multipartResolver"> <property name="defaultEncoding" value="UTF-8"></property> <!-- 上传文件的大小限制 ，单位是字节--> <property name="maxUploadSize" value="5242880000000"></property> <!-- 上传文件的临时路径，上传完成后会自动删除 --> <property name="uploadTempDir" value="upload/temp"></property> </bean> </beans>
（五）测试页面
<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> </head> <body> <h3>测试下载Excel功能</h3> <form action="file/download.htm" enctype="multipart/form-data" method="post"> <input type="submit" value="下载Excel"></input> </form> <h3>测试上传Excel功能</h3> <form action="file/upload.htm" enctype="multipart/form-data" method="post"> <input type="file" name="file"></input> <input type="submit" value="上传Excel"></input> </form> </body> </html>
如果想看完整源码，可以到我的Github仓库查看。 其中，上传文件只处理符合下载模板的文件。若要处理其它文件需要自实现。代码测试通过无误。
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持武林网。